John b



(No Model.)

J. B. TI BBITS.

ELECTRIC ARC LAMP. No. 287,067. Patented Oct. 23, 1883.

u. PETERS, Pholu-Lilhugnphfl, Waslvmglon, o. c.

UNITED STATES PATENT OFFICE.

JOHL B. 'TIBBITS, OF HOOSTO, NEXV YORK.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 287,067, dated Octolcer23, 1883,

Application filed February 15, 1883.

T0 aZZ whom, it may concern:

Be it known that 1, JOHN B. TIBBITS, of Hoosic, in the county ofRenssclaer and State of New York, have invented an Improvement inElectric Lamps, of which the following is a specification.

In are lamps the carbon has been acted upon by a solenoidcore, and twohelices have been usedone in the main circuit through the carhens andthe other in ashunt between the and *bindingpostsand in a priorapplication, filed September 27, 1882, I have shown a peculiar helix forfeeding the carbon and grasping the carbon-holder while drawing the are.

My present invention has for its object the more delicate adjustment ofthe forces that act upon the carbon, so that such forces may be balancedlike a scale and respond to the least difference of the resistance atthe are between the carbons. The helix employed forms a counterpoise tothe carbonholder and the solenoid acting on the same, the parts beingconnected by levers and links, by which both are suspended at oppositeends of the levers, and a frictional clamp is employed to grasp thecarbon-holder, and this frictional clamp is released sufficiently forthe carbon-holder to slide through it and lessen the distance be tweenthe carbon electrodes. set up by the current that passes through thesuspended helix or helices becomes one element in the balancing of theforces, because it acts to move the solenoid-core in either onedirection or the other and raise or lower the moving carbon at the sametime the helix itself moves in the opposite direction, thus dividing upthe motion and making the adjustment much more delicate than it could beif only one of the parts moved.

In the drawings, Figure l is an elevation, with part of the ease and themagnet in section; and Fig. 2 is a plan below the line 00 m. Fig. 3 is asimilar view, showing a movable weight applied to one of the levers.

The uppencarbon holder or red a passes vertically through the bottomplate, I), and

top plate, 0, of the case that contains the magnet. These plates b and care to be connected together by pillars or any suitable device, and

The magnetisni (X0 model-l the removable case J" protects the parts fromdust or dirt. I have shown the top plate, a, as provided with a socketto screw uponthe pipe 0 or other device for suspending the lamp andholding it in a vertical position.

The lower-carbon holder and carbon are made in any desired manner, andthey are supported in a frame that is fastened to the bottom plate, I).As myimprovement is available for almost any of the known forms of lamp,I have not shown the frames or the carbons supporting the lower-carbonholder.

Around the carbon-holder I place the tubular solenoid-core e, and thesame is within a spool, F, that has two helices wound upon it, the helixG being of coarse wire, and the helix H of fine wire. The levers 1? 7tarepivoted upon hanging brackets below the top plate, 0, orin any othersuitable manner, and the linksl connect the outer ends of these leversto joints or upon the spool F, and the links a connect the inner ends ofthese levers to joints 0 upon the top of the solenoid-core c.

The carbon-holding rod a is guided between f1lGtlO1l-lOllC1S p, which,foreouvenience, are upon the pivot-pins of the lovers 2 7., and theparts are so proportioned that the spool F and helices will nearlycounterbalance the solenoid-core and the carbon-holder.

Around the carbon-holder there is a clamp, ur, which by preference iscomposed of a helix of wire. or of two helices, the ends of which areconnected to a small weight, 0, and to the solenoid, respectively, as ats and 8, this clamp being similar to that shown in my aforesaidapplication.

, I place around the carbon-holder and below the weight '1- a yieldingrest composed of awasher, 1, with a spring, t, below it. The currentpasses from any suitable conductor to the insulated binding-post p,thence by wire 1 to the wire ot'the helix G, and a shunt-wire, q, passesto the fine-wire helix H, thence by a wire, (1, to the negativebinding-post c. The other end of the helix G- passes to the wire '0, andthence to the lower-carbon holder, and the current traverses thecarbons, and by the upper-carbon holder and the rollers 7) reaches thetop plate, (1, and negative binding-post.

The wires between the helices G and H and wire.

The operations of the parts are as follows: The current passing throughthe helices G H differentially sets up magnetism that acts on thesolenoid-core. When the magnetism in G increases it tends to draw up thesolenoid-core, and by the helical clamp lift the carbon-holder a andupper carbon. When the magnetism in H increases, it tends to draw downthe core 0, and thereby feed the carbon. These forces act in the usualmanner in differential magnetsthat is to say, when the electric arebetween the carbons lengthens in consequence of the carbons beingconsumed or breaking off, the current in G lessens in consequence of thegreater resistance, and it increases in shunthelix H and acts to drawdown the solenoid and feed the carbons. It will, however, be apparentthat the levers t k and links l n connect the core and helices; hencethe core cannot be drawn down by the magnetism without the helix goingup at the same time, and the reverse; hence the action and reaction aresubdivided and rendered of the most delicate character. As soon as theweight 1' at the lower end of the helix rests upon the springwasher t,the helix is expanded by being shortened" in length by the movement ofthe core;

hence the frictional grasp of the helix on the carbon-holder islessened, and the latter slips lamp occupy a certain normal positionwhen the lamp is burning, and the feed is frequent and very small, andgreat uniformity is attained. When the lamp is not burning, the uppercarbon descends by gravity, together with the solenoid-core, and the arcis drawn by the magnetism set up by the current in G, raising thesolenoid-core. If aheavier solenoid-core is required, the same may bemade longer than the spool, and it will act in the same manner as theshorter core.

If desired, the fulcrum of the levers may be nearest their outer ends,so as to give greater leverage to the core in suspending the spool Ifdesired, the fulcra may be made adjustable, or the pivots by which thelinks Z n are connected to the levers k 13 may be movable, so as to varythe leverage and adjust the balance. The same object may be attained 'byextending either or both levers k i in the form shown in Fig. 3 and bydotted lines in Fig. 1, so that a movable weight, k may be placed uponeither end, and adjusted so as to properly balance the respective partsand cause the carbons to rest upon each other previously to beinglighted, and to draw apart when the current is applied.

I claim as my invention- 1. The combination, with the carbon-holder inan electric lamp, of a core, a helix, levers, and connections by whichthe parts are balanced, and the core moves in one direction as q thehelix moves in the other direction, and a clamp acting upon thecarbon-holder rod and being acted upon by the solenoid, substantiallyasset forth.

2. The combination, with a carbon-holder rod in an electric lamp, of atubular solenoidcore surrounding the rod, a helical clamp around the rodand within the core, a connection at the top of the helical clamp to thecore, a weight connected at the lower end of the helical clamp, and ayielding rest for the weight, substantially as set forth.

3. In an electric-arc lamp, two helices upon one spool-one of coarse,the other of fine, Wireleversand links for suspending such spool, asolenoid-core within the spool, links connecting the same to saidlevers, a carbonholding rod, and a clamp for holding and moving suchrod, and a connection between the clamp and the solenoid, substantiallyas set forth.

4. In an electric-arclamp, a carbon-holding rod supported and movingvertically, a tubular solenoid-core around the same, a clamp connectedto said solenoid-core and acting on the rod, a spool and differentialhelices around the solenoid-core, circuit-connections to thedifferential helices and carbons, a lever, and variable connectionsbetween the lever and spool or solenoid, so as to afford a ready meansfor balancing the respective parts, substantially as specified.

Signed by me this 5th day of February, A. D. 1883.

JOHN B. TIBBITS.

Witnesses:

F. P. UMETRANO, B. MACGREGOR.

